1. Field of the Invention
The present invention relates to a process for preparing a polyolefin. More particularly, it relates to a process for preparing a polyolefin by polymerizing an olefin such as ethylene, propylene, butene-1 etc., in the presence of a catalyst having high catalytic activity comprising an organoaluminum compound and a carrier supported catalytic component.
2. Description of the Prior Art
Heretofore, it has been proposed to use various carrier supported catalytic component for a polymerization of an olefin. For example, it has been proposed, for the polymerization of ethylene to use a solid catalytic component prepared by reacting a titanium halide or a vanadium halide with a reaction product of .alpha.,.omega.-dihyroxydimethyl polysiloxane or diphenylsilane diol, etc. with a Grignard reagent in U.S. Pat. No. 3,907,759. However, when these catalysts are used, the stereospecific properties of the resulting polymers prepared by polymerizing an olefin especially propylene or butene-1, are remarkably low and the industrial value is not enough high.